Boosted charge transfer and Na-ion diffusion in cooling-fins-like Sb2Te3-Te nano-heterostructure for long cycle life and high rate capability anode

Abstract To improve the electronic conductivity and accelerate the Na-ion diffusion in active materials for sodium-ion batteries (SIBs), Sb2Te3-Te nano-heterostructure (STNH) electrodes are constructed based on the hierarchical nanostructures of two-dimensional (2D) Sb2Te3 nanoblades serialized by one-dimensional (1D) Te nanowires for high-performance anode material. The STNH electrode can deliver high sodium storage capacity of 375 mAh g-1 at 100 mA g-1 after 200 cycles and provides a capacity of 226 mAh g-1 at 15 A g-1, even can obtain a high capacity of 365 mAh g-1 at 1.5 A g-1 after 1000 cycles, respectively. The sodiation/desodiation reaction mechanism is also investigated by ex-situ selected-area electron diffraction (SAED) and in situ X-ray diffraction (XRD). The enhanced sodium storage properties of STNH are mainly attributed to the integrated merits of both 1D and 2D with enhanced charge carrier migration and good structure stability. This work gives the rational guidance to design novel hierarchical nanostructures integrating 1D and 2D nano-heterojunction materials for advanced battery materials. The as-designed STNH electrode enhances sodium storage with potential interest in SIBs.